Knurling tool



Patented Aug. 19, 1941 KNURLING TOOL Walter A. Heinrich, RichmondHeights, Men, as-

signer to James R. Kearney Corporation, St. Louis, Mo., a corporation ofMissouri Application March 23, 1939, Serial No. 263,653

2 Claims.

This invention relates generally to tools adapted for use in splicingtogether lengths of elon gated material, and more specifically to such atool which may be employed to connecttogether lengths of electric wirein a manner to produce .whichbecause of its improved construction andarrangement is capable of performing its in. tended function in animproved and highly efficient manner.

Fig. 1 is a front elevation of the improved tool.

Fig. 2 is an edge elevation of the tool illustrated in Fig. 1.

Fig. 3 is a fragmentary front elevation illustratinga part of the modeof using the improved tool.

Fig. 4 is an enlarged cross-section taken on line 4-4 of Fig. 3.

Fig. 5 is a fragmentary view illustrating a joint between a pair oflengths of electric wires showing said joint as it appears when theoperation of making said joint with the aid of the improved tool hasbeen partially completed.

Fig. 6 is an enlarged perspective showing the manner of completing ajoint between a pair of lengths of electric wires with the aid of theimproved tool.

In the drawing, wherein is shown for the purpose of illustration,merely, one embodiment of the invention, A designates the improved toolgenerally. The tool A comprises a pair of elements I and 2 which areconnected together for relative pivotal movement by means of a pivotmember 3 which extends through apertures formed through said elements. IAt corresponding ends of the elements I and 2 said elements are providedwith crimping jaws 4 and 5 which have formed therein arcuate cavities 4and 5' respectively. The elements I and 2 are provided also with spacedhandle portions 6 and I which provide for proper gripping of the tool bya user thereof.

As shown to the best advantage in Fig. 2 the overlapping portions I' and2' through which the pivot member 3 extends are approximately one-halfof the normal thickness of the ele ments, and formed on the thickerportion of the element I is an inclined face 8. .The element 2 is alsoprovided with an inclined face 9 and said faces 8 and 9 are so formed onthe elements I and 2 and are so related that a channelway I0 is providedbetween said inclined faces. Also the elements I and 2 are provided withcurved cavities II and I2 opening into said channelway ID in whichcavities rollers I3 and I I are arranged, said rollers being mounted forrotary movement on pins I5 and I6 whichare provided with enlarged headsand include shank portions I5 and I6 of reduced diameter that are driveninto openings formed in the elements I and 2. The rollers I3 and I I areprovided with knurled circumferential faces and said rollers locatedentirely within the cavities II and I2 so that no portions thereofextend beyond the normal surface of the tool.. Asshown in Figs. 1 and 3the rollers I3 and I4 are so positioned that an imaginary line extendedfrom the axis of one of the rollers to the axis of the other rollerwould be extended. at an approximate right angle to the channelway I0,and said channelway is in alinement with the space between the rollersI3 and I4 when said rollers are in their operative positions.

In the use of the improved tool the handle portions 6 and I are spreadapart slightly and an end portion of a length of wire W, which is to beconnected to another length of wire with the aid of the tool, isextended through the channelway ID as shown in Fig. 3, the insulation ofsaid wire having been stripped from the end portion I of the wire asindicated at W in Fig. 3. The handle portions of the tool are then movedtoward each other to cause the rollers I3 and I4 to contact withconsiderable force against the I stripped end portion of the wire atpoints inwardly of the outer end thereof. The wire W is then grasped andheld while the tool is moved longitudinally of the stripped end portionof the wire toward the outer end thereof, with the knurledcircumferential faces of the rollers I3 and I4 maintained in closecontact with the stripped end portion of the wire by inward pressure onthe handle portions of the tool. Such movement of the tool with respectto the stripped end portion of the wire W will cause the rotatingrollers I3 and I4 to roughen surface portions of the stripped endportion of the wire as indicated at I! in Fig. 5. The other length ofwire W to be connected with the aid of the tool is then similarlyprepared through use of the tool, the stripped end portion W thereofbeing provided with roughened surface portions IT as shown in Fig. 5.

When the stripped end portions of the two lengths of wire have beenprepared as described the stripped ends of the lengths of wire areinsorted into opposite ends of a sleeve S formed of copper or othersuitable material as shown in Fig. 5, and the tool is employed to crimpthe sleeve S at points spaced longitudinally of said sleeve as shown atC in Fig, 6. The crimps C are formed by forcing the handle portions ofthe tool toward each other to cause the crimping jaws 4 and 5 to engagesaid sleeve and displace the metal of said sleeve as shown in Fig. 6.some of said displaced metal being forced into portions of the spacebetween the crimping jaws whereby the opposed fin-like extensions C areformed. Due to the crimping of the sleeve S the inner face of saidsleeve is caused to contact tightly with the surfaces of the strippedend portions of the lengths of wire being connected with the aid of thetool, and because portions of the surfaces of said stripped end portionshave been roughened by contact of the knurled rollers l3 and I4therewith a better mechanical gripping action between the sleeve and thestripped end portions of the lengths of wire is provided.

'An important feature of the invention disclosed herein is that theelements 6 and l of the tool A are provided with cooperating abutmentsl8 and H! which contact with each other when the handle portions 6 and lare moved toward each other to the inward limits of their movement. Whenthe abutments l8 and id have moved into contact With each other thecrimping jaws 4 and 5 and the knurled rollers 13 and M are stillmaintamed in slightly spaced relation as shown in Fig. 1. By somaintaining the crimping jaws and the knurled rollers in spaced relationwhen the handle portions of the tool are brought together battering ofthe crimping jaws and the surfaces ofthe rollers, which would resultfrom repeated and forcible contact of'said parts in the absence of theabutments l8 and 1! 9 is prevented.

I claim: v

1. A tool of the class described comprising a pair of elements havinghandle portions, means for connecting said elements together for pivotalmovement, knurling rollers supported by said elements for rotarymovement, said rollers being completely exposed at a side of the tooland being movable toward and from each other with said pair of elementsupon relative movement thereof, and inclined faces formed at outersurfaces of said elements which provide a channelway leading betweensaid rollers which serves to guide an article being knurled by the tool,said channelway being extended at an angle relative to the longitudinalaxis of the tool and said channelway being open at the side of the toolat which the rollers are exposed throughout its entire length so thatthe entire operation of knurling an article with the aid of the tool maybe viewed by a user of the tool.

2. A tool of the class described comprising a pair of elements havinghandle portions; means for connecting said elements together forpivotalmcvement, knurling rollers supported by said elements for rotarymovement, said rollersbeing completely exposed at a side of the tool andbeing movable toward and from each other with said pair of elements uponrelative movement thereof and inclined faces formed at outer'surfaces ofsaid elements which provide-a channelway'leading between said rollerswhich serves. to guide an article being knurled'by the tool, said chanbya user of the tool, said knurling rollers being disposed in cavitiesformed in said elements which are in communication with said channelway.

WALTER 'A. HEINRICH.

